prototype string for a km3 baikal neutrino telescope
DESCRIPTION
Prototype string for a km3 Baikal neutrino telescope Roma International Conference on Astroparticle Physics. V .Aynutdinov, INR RAS for the Baikal Collaboration. Roma, June 2007. Collaboration. Institute for Nuclear Research, Moscow, Russia. - PowerPoint PPT PresentationTRANSCRIPT
Prototype string Prototype string for a km3 Baikal neutrino telescopefor a km3 Baikal neutrino telescope
Roma International Conference on Astroparticle PhysicsRoma International Conference on Astroparticle Physics
VV.Aynutdinov, INR RAS .Aynutdinov, INR RAS for the Baikal Collaborationfor the Baikal Collaboration
Roma, June 2007Roma, June 2007
Institute for Nuclear Research, Moscow, Russia.
Irkutsk State University, Russia.
Skobeltsyn Institute of Nuclear Physics MSU, Moscow, Russia.
DESY-Zeuthen, Zeuthen, Germany.
Joint Institute for Nuclear Research, Dubna, Russia.
Nizhny Novgorod State Technical University, Russia.
St.Petersburg State Marine University, Russia.
Kurchatov Institute, Moscow, Russia.
CollaborationCollaboration
OutlineOutline1. Introduction Objectives of prototype string installation
2. Prototype string design
3. Prototype string as a part of NT200+, modernization of NT200+ data acquisition system
4. Preparative works (2007) - prototype of a FADC based system - new optical module - PM selection for the km3 prototype string
Summary
Introduction
FA DC
OM3
OM1
OM2
OM6
OM4
OM5
OM3
OM1
OM2
OM6
OM4
OM5
Project of km3 BaiaklNeutrino Telescope
NT200+current statusPrototype
string
Installation of a “new technology”
prototype string as a part of NT200+ (spring 2008)
Investigations and in-situ tests of basic knots of future detector: optical modules, DAQ system, new cable communications.
Studies of basic DAQ/Triggering approach for the km3-detector.
Confrontation of classical TDC/ADC approach with FADC readout.
Design of Prototype string Design of Prototype string
PMT pulses & Power 12 VControl line
Data (Ethernet), Trigger
FA DC
P Csphere
OM4
OM6
OM5
FA DC
OM3
OM1
OM2
OM6
OM4
OM5
OM1
OM3
OM2
PC-104
RS485c onv er
ter
DSL
modem
RS485c onv er
terEth
Sw itc h
Tr iggerc ontro l
VME
Contr
FADC9
101112
FADC5678
FADC1234
Power
Trigger
Multic hannel A mplif ier&Pow er output
PMT
D iv id e r /A m p lif ie r
C O N T R O L L E R O M-M C C 8 0 5 1 F 1 2 4-R S 4 8 5 in te r fa c e-P M T p u ls e c o u n te r-P o w e r (H V , L V ) m o n ito r
H V U N ITP H V 1 2 -2 .0 K
LEDs
L E Dc o n tr o l- A m p l- D e la y
Basic features
String lengths ~300 m
String contains 12…16 OM
Optical modules contains only PM and control electronics
12 bit 200 MHz FADC readout is designed as multi channel separate unit.
Half-string FADC controllers with ethernet-interface connected to string PC unit
String PC connected by string DSL-modem to central PC unit
30
0 m
FADC unit is operating nowin Tunka detector(astro-ph/0511229)
Prototype string as a part of NT200+Modernization of data acquisition system during expedition 2007
Basic goal of DAQ Basic goal of DAQ modernization is increase of modernization is increase of the uw-data rate:the uw-data rate:- Transmission FADC data;- Transmission FADC data;- Trigger algorithm Trigger algorithm optimizationoptimization
2005: data/control TCP/IP 2005: data/control TCP/IP connection between the connection between the shore station and central uw-shore station and central uw-PCs.PCs.
2007: TCP/IP communication 2007: TCP/IP communication between uw-PCs and string between uw-PCs and string controller.controller.
Time synchronization: Time synchronization: measuring of each string measuring of each string trigger time with 2 ns trigger time with 2 ns precision).precision).
2-wire DSL-modem line
String trigger
4-wire Ethernet line
NT200
str1 str2
str3
Pstr
DSLTrig
PC
DSL
CNT
ADC
TDC
DSL-modem
New string controller- Ethernet interface- TDC/ADC readout
Prototype string- 2 FADC sphere- PC sphere
10
00
m
To shore (DSL-modem line, 1 Mbit)
1 channel
Time (nsec)3 7003 6003 5003 400
Am
plitu
de (
V)
0.11
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
1 channel
Time (nsec)700600500400
Am
plitu
de (
V)
2.2
2.1
2
1.9
1.8
1.7
1.6
1 channel
Time (nsec)3002001000
Am
plitu
de (
V)
2
1
0
Prototype of FADC based systemPrototype of FADC based system2-channel FADC prototype was installed during expedition 2-channel FADC prototype was installed during expedition 20072007
Purposes:Purposes:- optimal sampling time window- optimal sampling time window- dynamic rangedynamic range- obtainable pulse parameter precision obtainable pulse parameter precision -algorithms for online data handlingalgorithms for online data handling
Examples of FADCExamples of FADCpulses for differentpulses for differentclasses of events:classes of events:1.1. One p.e. noise One p.e. noise
hithit2.2. A muon trigger A muon trigger
(multi-p.e.)(multi-p.e.)3.3. Backward Backward
illumination by a illumination by a calibration lasercalibration laser
PMs R8055
FADC 250 MSPS
New optical module (OM)New optical module (OM)
1. New PMT: R8055, XP1807, … : ~20 ns FWHM2. Control and monitoring system inside OM: HV value, power supply, PMT noise rate, temperature. 3. 2-LED calibration system for operation with FADC: LED amplitude and pulse delay control: dynamic range >108, delay range 0…1000 ns (+/- 1 ns).
OM NT200+ NEW OM designed
for km3 Baikal telescope
PMT
D iv id er /A m p lif ie r
C O N T R O L L E R O M-M C C 8 0 5 1 F 1 2 4-R S 4 8 5 in ter fa c e-P M T p u ls e co u n ter-P o w er (H V , L V ) m o n ito r
H V U N ITP H V 1 2 -2 .0 K
LEDs
L E Dco n tr o l- A m p l- D e la y
1. Hybrid photodetector Quasar-370: ~80…100 ns FWHM2. Outer control system3. 25 kV Quasar power supply4. 1-LED calibration
0,1 1 100,15
0,20
0,25
0,30
0,35
0,40
0,45
<y>=0.36 (0...2,5 V)
y=s2 /Q
, nV
s
A, Volt
0,0 2,0x10-10
4,0x10-10
6,0x10-10
8,0x10-10
0
50
100
150
200
Eff=0.21
<Q1e>=2.55x10-10 Vs
r2=<Q2>/<Q>2=1.36
N
Q, Vs1,2x103
1,4x103
1,6x103
1,8x103
0,1
1
10
A
Q
Q, n
Vs;
A, V
HV, V
PM monitoringPM monitoringwith one LEDwith one LED
PM monitoringPM monitoringwith two LEDwith two LED
PM parameter monitoring PM parameter monitoring with new OM control systemwith new OM control system
1 100,6
0,7
0,8
0,9
1,0
1,1
Q1+
2 /(
Q1+
Q2)
A1+A
2, V
Pulse area and amplitude dependence's on HV value
2/Q dependence on pulseamplitude (s2/Q ~ Gain_of_PM)
Single electron PM spectrum
PM linearity test with 2 LEDs (1% precision)
PM selection for the km3 prototype stringPM selection for the km3 prototype stringBasic criteria of PM selection is its effective sensitivity to Cherenkov Basic criteria of PM selection is its effective sensitivity to Cherenkov
light: fraction of registered photons per photon flux unit. light: fraction of registered photons per photon flux unit. ((Photocathode areaPhotocathode area Quantum efficiency Quantum efficiency Collection efficiency) Collection efficiency)
Quasar-370 D 14.6”Quantum efficiency 0.15
Hamamatsu R8055 D 13”Quantum efficiency 0.20?? ??
Photonis XP1807 D 12”Quantum efficiency 0.24
PM selection : Laboratory testsPM selection : Laboratory tests
PMPMss R8055, R8055, ХХP1807, Quasar-370 P1807, Quasar-370
1.5 m
Diffusor
10 20 30 40 50 600,0
0,2
0,4
0,6
0,8
1,0
1,2
Npe
(H22
8) /
Npe
(Q
1023
)
Npe
10 20 30 40 50 600,0
0,2
0,4
0,6
0,8
1,0
1,2
Npe
(H22
8) /
Npe
(P10
06)
Npe
LED LED 470 нм, 5 нс 470 нм, 5 нс FWHMFWHM
Examples of relative sensitivities measurements for Quasar-370, R8055, and XP1807
4 PM R8055 4 PM R8055 (Hamamatsu) (Hamamatsu) и 2 и 2 XP1807 (Photonis)XP1807 (Photonis)were installed to were installed to NT200+ detector (April NT200+ detector (April 2007).2007).
4 PM: central telescope 4 PM: central telescope NT 200;NT 200;2 PM R8055: outer 2 PM R8055: outer string,string, FADC prototype.FADC prototype.
Quasar-370Quasar-370
Quasar-370Quasar-370
Quasar-370Quasar-370
Quasar-370Quasar-370
R8055R8055
XP1807XP1807
PM selection: Underwater testsPM selection: Underwater tests
LaserLaser
160…
180 m
Ratio of effective sensitivities of large area PMsRatio of effective sensitivities of large area PMs(preliminary results)(preliminary results)
0 1 2 3 4 5 60,0
0,2
0,4
0,6
0,8
1,0
1,2
1,4
XP1807 #1026
XP1807 #1006 R8055
#186 R8055 #314
R8055 #228
Quasar-370
Rel
ativ
e P
M s
ensi
tiviti
es
PMT number
Ratio of effective sensitivity of large area PMs R8055/13” and XP1807/12” to Quasar-370/14.6”. Laboratory (squares), in-situ (dots).
Smaller size (R8055, XP1807) tends to be compensated by larger photocathode sensitivities.
SummarySummary
1.1. For the planned km3-detector in lake Baikal, R&D-For the planned km3-detector in lake Baikal, R&D-activities have been started.activities have been started.
2.2. The existing NT200+ allows to verify all key elements The existing NT200+ allows to verify all key elements and design principles of km3-detector.and design principles of km3-detector.
3.3. Modernization of NT200+ DAQ system allowed to Modernization of NT200+ DAQ system allowed to install a prototype FADC PM readout at spring 2007.install a prototype FADC PM readout at spring 2007.
4.4. Six large area hemispherical PM (2 Photonis XP1807 Six large area hemispherical PM (2 Photonis XP1807 and 4 Hamamatsu R8055) have been integrated into and 4 Hamamatsu R8055) have been integrated into NT200+ to facilitate the optimal PM choice.NT200+ to facilitate the optimal PM choice.
5.5. A full scale “new technology” prototype string will be A full scale “new technology” prototype string will be installed in spring 2008 as a part NT200+.installed in spring 2008 as a part NT200+.